xref: /linux/arch/powerpc/include/asm/module.h (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 #ifndef _ASM_POWERPC_MODULE_H
3 #define _ASM_POWERPC_MODULE_H
4 #ifdef __KERNEL__
5 
6 #include <linux/list.h>
7 #include <asm/bug.h>
8 #include <asm-generic/module.h>
9 
10 #ifndef __powerpc64__
11 /*
12  * Thanks to Paul M for explaining this.
13  *
14  * PPC can only do rel jumps += 32MB, and often the kernel and other
15  * modules are further away than this.  So, we jump to a table of
16  * trampolines attached to the module (the Procedure Linkage Table)
17  * whenever that happens.
18  */
19 
20 struct ppc_plt_entry {
21 	/* 16 byte jump instruction sequence (4 instructions) */
22 	unsigned int jump[4];
23 };
24 #endif	/* __powerpc64__ */
25 
26 
27 struct mod_arch_specific {
28 #ifdef __powerpc64__
29 	unsigned int stubs_section;	/* Index of stubs section in module */
30 #ifdef CONFIG_PPC_KERNEL_PCREL
31 	unsigned int got_section;	/* What section is the GOT? */
32 	unsigned int pcpu_section;	/* .data..percpu section */
33 #else
34 	unsigned int toc_section;	/* What section is the TOC? */
35 	bool toc_fixed;			/* Have we fixed up .TOC.? */
36 #endif
37 
38 #ifdef CONFIG_PPC64_ELF_ABI_V1
39 	/* For module function descriptor dereference */
40 	unsigned long start_opd;
41 	unsigned long end_opd;
42 #endif
43 #else /* powerpc64 */
44 	/* Indices of PLT sections within module. */
45 	unsigned int core_plt_section;
46 	unsigned int init_plt_section;
47 #endif /* powerpc64 */
48 
49 #ifdef CONFIG_DYNAMIC_FTRACE
50 	unsigned long tramp;
51 	unsigned long tramp_regs;
52 #ifdef CONFIG_PPC_FTRACE_OUT_OF_LINE
53 	struct ftrace_ool_stub *ool_stubs;
54 	unsigned int ool_stub_count;
55 	unsigned int ool_stub_index;
56 #endif
57 #endif
58 };
59 
60 /*
61  * Select ELF headers.
62  * Make empty sections for module_frob_arch_sections to expand.
63  */
64 
65 #ifdef __powerpc64__
66 #    ifdef MODULE
67 	asm(".section .stubs,\"ax\",@nobits; .align 3; .previous");
68 #        ifdef CONFIG_PPC_KERNEL_PCREL
69 	    asm(".section .mygot,\"a\",@nobits; .align 3; .previous");
70 #        endif
71 #    endif
72 #else
73 #    ifdef MODULE
74 	asm(".section .plt,\"ax\",@nobits; .align 3; .previous");
75 	asm(".section .init.plt,\"ax\",@nobits; .align 3; .previous");
76 #    endif	/* MODULE */
77 #endif
78 
79 #ifdef CONFIG_DYNAMIC_FTRACE
80 int module_trampoline_target(struct module *mod, unsigned long trampoline,
81 			     unsigned long *target);
82 int module_finalize_ftrace(struct module *mod, const Elf_Shdr *sechdrs);
83 #else
84 static inline int module_finalize_ftrace(struct module *mod, const Elf_Shdr *sechdrs)
85 {
86 	return 0;
87 }
88 #endif
89 
90 #endif /* __KERNEL__ */
91 #endif	/* _ASM_POWERPC_MODULE_H */
92